Vehicle racetracks are used for car and motorcycle racing at speeds in excess of 350 Km/hr. At such speeds, even a minor suspension or tyre failure can cause a vehicle to leave the track with considerable forward and transverse speed. Should a throttle jam open, the result is even more spectacular. Small amounts of water or oil on the track can also be catastrophic.
Not all vehicles that depart a track are irretrievably lost to a race. Many vehicles can return to the track to continue a race. The present invention seeks to provide a vehicle arresting apparatus, which is more effective in transfer of kinetic energy, and less damaging to the vehicle than prior art solutions, thereby to enable a higher proportion of arrested vehicles to return to a race track or the proper carriageway.
It is a feature of racing vehicles that ground clearance is kept to a minimum to reduce drag and increase aerodynamic partial vacuum adhesion to the racing track. Wheel intrusion beyond the lower surface of the body is very small.
Prior art includes the provision of gravel (or other aggregate) beds adjacent to a track so that a vehicle has its wheels retarded by imparting kinetic energy to the individual particles of gravel or aggregate, Unfortunately, because of the low vehicle body to ground clearance, the wheels hardly penetrate the gravel or aggregate and the vehicle tends to skim over the surface of the gravel or aggregate on the underside of its body. The size of the gravel or aggregate bed has to be made disproportionately long and wide to ensure dissipation of all longitudinal and transverse kinetic energy. The present invention seeks to provide means for arresting a vehicle where dimensions of the arresting medium are kept to a minimum, without loss of effect and minimising vehicular damage.
When in the arresting medium, the slowing vehicle can cast up large amounts of the medium in the direction of travel, which is, generally, in a direction away from the track. The kinetic energy of such ejected material is considerable. Gravel and aggregate can be hurled in the direction of spectators, track officials and nearby objects, causing damage and injury. An equal hazard appears when an undamaged, arrested vehicle seeks to return to the track. Low friction and wheel spin can cast up material, not only away from the track, but also in the direction of oncoming vehicles. Ejected matter can lie on the track. The present invention seeks to provide apparatus where such potentially damaging ejection of material is avoided, thereby permitting the spectators to be nearer to the track without loss of protection.
Flying solid particles can injure the driver or other occupants of the vehicle. This is especially true if the vehicle should overturn. The present invention seeks to minimise injury to vehicle occupants.
A vehicle, which is damaged upon leaving a track, requires track service vehicles and equipment to recover the crashed vehicle and provide any medical or fire service attention that may be required. Gravel and aggregate impede access to the crashed vehicle and are further churned up by their progress. The present invention seeks to provide a vehicle arrest apparatus, which readily allows service vehicles access to the crashed vehicle.
When a vehicle has been arrested by gravel or aggregate, the arresting medium requires maintenance before it is in a correct condition to receive a further vehicle. Gravel and aggregates require to be retrieved and re-distributed. Such maintenance is hazardous during a race, requires partial road closure for an ordinary roadway, and is costly long-term. The present invention seeks to eliminate the need for such maintenance and to provide vehicle-arresting apparatus which instantly returns to a state of readiness to arrest a further vehicle.
Vehicle race tracks cater for all types of vehicles. Some types of vehicle, notably motorcycles, respond best to being arrested using a gravel or aggregate arresting medium, while others respond best to being arrested according to the present invention. The present invention seeks to provide an apparatus which can rapidly and automatically be converted to use of a gravel or aggregate arresting medium, thereby avoiding delays and labour costs between different sorts of track events.